fix: enum on python2

Author: lihsai0

qiniu/compat.py

@@ -36,9 +36,7 @@
     from urllib import urlencode  # noqa
     from urlparse import urlparse  # noqa
     import StringIO
-    import enum34
     StringIO = BytesIO = StringIO.StringIO
-    Enum = enum34.Enum
 
     builtin_str = str
     bytes = str
@@ -65,10 +63,8 @@ def is_seekable(data):
 elif is_py3:
     from urllib.parse import urlparse, urlencode  # noqa
     import io
-    import enum
     StringIO = io.StringIO
     BytesIO = io.BytesIO
-    Enum = enum.Enum
 
     builtin_str = str
     str = str

qiniu/http/region.py

@@ -1,6 +1,6 @@
 from datetime import datetime, timedelta
 
-from qiniu.compat import Enum
+from enum import Enum
 
 from .endpoint import Endpoint